I want this because the activation email seems to work ok only for gmail accounts and the hotmail accounts do not receive the email (I have tried the mail plugins suggested in the codex). But I also would like to make the registration process shorter and super simple to my potential users.

If the sent email can not be removed, maybe replacing the activation key with a welcoming message.

I know that if I do this, the site would be vulnerable to sploggers but I have seen there are safety plugins for this such as wangward.

About my issue: I changed hosting, it appears that buddypress and banahosting do not get a long as nicely as I would like to. The support people were nice and polite, but could not resolve the issue with the email fast enough.

I also add that the BP-Disable-Activation works but, I deactivated it because I do not want a lot of unnecesary plugins.